Paul Tooke may have some better partial patterns and has likely put some serious search time in on this problem.

My only idea is to take a partial pattern with a small width, like the partial I posted near the front where the blinkers are, and try to extend the pattern in different directions. I have not had any success with this.It may also be useful to learn more about how the c/7 diagonal ship was discovered.

Paul Tooke may have some better partial patterns and has likely put some serious search time in on this problem.

According to my records that is incorrect on both counts. The only searches I did for c/7 orthogonal spaceships were a few narrow width gfind searches back in 2000. That was before I had added the state-saving code, so I have no partial patterns.

I do remember at one time trying searches with the search tree initialized with partial patterns consisting of the beehive-push from the Dragon (It can happen at c/N for N>=6). This is similar to the front end of Hartmut's partial result. Unfortunately, I don't appear to have retained any records of the seaches or any partial patterns.

I believe that Hartmut is right. Technology has moved on and it may be that there are things to be found by someone who is prepared to devote a good chunk of CPU time to the effort.

Shows that there are probably other similar surprizes still lurking around to be found…

I find interesting how the two halves interact only marginally, seems like there could be potential for a further grammar of components. E.g. two copies of the lower portion make up a symmetric 16-cell spaceship if birth from 4 diagonal neighbors is allowed…

I should add that I found this with WLS. I found the smaller half a while ago, but couldn't finish a spaceship with it. This thread encouraged me to keep looking. In my searches WLS found the second half and completed the ship with the first half I had found earlier. It's entirely possible that there are other ships which use these parts. I was very surprised how small this ship was, and had to recheck several times that I had been searching with the right settings.Thanks for coming up with a glider synthesis so quickly. It's not every ship that has a synthesis.

Congratulations to a really awesome c/7 ship, I would never believe that such a small object could avoid being found in myriads random soup/random agar searches performed so far. I had to check the rule twice before I believed that it's really running in the standard GoL rule...Congratulations!

velcrorex wrote:Thanks for coming up with a glider synthesis so quickly. It's not every ship that has a synthesis.

You can say that again! Hardly *any* spaceships have syntheses, let alone such straightforward ones. This will fairly quickly require an update the whole (1,0)c/7 line in Jason Summer's table of spaceship velocities. Except maybe the "wickstretcher" cell -- anyone know if there are any likely wick candidates at c/7?

"Versatile puffer" will take a while, too, I suppose. But from the look of the two parts of that c/7 ship, with interaction in only one tick out of the seven, it certainly seems as if new combinations and tagalongs with usable sparks might appear in fairly short order.

Edit: I looked again, and it's not quite that simple a connection; there's some interaction between the halves in two successive ticks. Still seems like a good bet that there are more variants out there!

-- Do you have a name yet for these wonderful new Life forms? I'm thinking of them as "loafers" until you come up with something official.

dvgrn wrote:from the look of the two parts of that c/7 ship, with interaction in only one tick out of the seven, it certainly seems as if new combinations and tagalongs with usable sparks might appear in fairly short order... I looked again, and it's not quite that simple a connection; there's some interaction between the halves in two successive ticks. Still seems like a good bet that there are more variants out there!

I have seen the smaller part of this spaceship in my own searches, and it has other simple connections that might lead to new ships:

On this note, I think I have eliminated the possibility of a height 8 c/7 orthogonal spaceship (I'd like independent confirmation before I say anything definite), but starting with one of the parts of this new spaceship may be a quick way to find something taller. Has anyone ruled out the possibility of a width 9 spaceship of this speed?

Still, we might be as well off trying to find new c/6 orthogonal spaceships, as we still don't have any puffers for that speed. A good starting point might be the following subpattern, which occurs in two of the known c/6 orthogonal spaceships:

There are zillionplexes of 20-cell patterns, and most of them are going to occur naturally incredibly rarely. Besides, oscillators and slow spaceships will presumably have less of a chance of being detected than faster ones, due to lesser chances of survival. If soup searches DO turn up a non-standard spaceship eventually, I bet it would be faster than this one.

Sokwe wrote:Still, we might be as well off trying to find new c/6 orthogonal spaceships, as we still don't have any puffers for that speed.

From around p7-ish, 2c/6 is also a search option.

(Also I've said this before, but the fact that the four natural spaceships AND the switch engine are all glide-reflective makes me wonder how so few glide-reflective "artificial" ships have been sought yet.)

I really like Dave Greene's name for this ship, "loafer", as it describes both its slow movement, and the fact that it pushes a loaf. @Velcrorex, what do you think?

Tropylium wrote:The fact that the four natural spaceships AND the switch engine are all glide-reflective makes me wonder how so few glide-reflective "artificial" ships have been sought yet.

The problem with such spaceships is they are limited to even periods greater than 2, so they quickly become difficult to search for. Since 4 is a reasonably small period, we have been able to find many glide symmetric c/2 orthogonal and c/4 diagonal ships. There have been a number of p6 c/3 glide symmetric ships using p3 supporting components, but beyond this, these are the only ships I know of where the glide symmetric component was found directly (first by Jason Summers, middle two by Nicolay Beluchenko, last by Josh Ball):

Tropylium wrote:The fact that the four natural spaceships AND the switch engine are all glide-reflective makes me wonder how so few glide-reflective "artificial" ships have been sought yet.

The problem with such spaceships is they are limited to even periods greater than 2, so they quickly become difficult to search for.

Why does the period matter though? I mean, if searching for these in particular, obviously you wouldn't just scour the whole search space and hope that any results had some extra symmetry, but set an obvious symmetry restriction in place to begin with. Thus standard spaceships should be found in a p2 search, etc.

Tropylium wrote:Why does the period matter though? I mean, if searching for these in particular, obviously you wouldn't just scour the whole search space and hope that any results had some extra symmetry, but set an obvious symmetry restriction in place to begin with. Thus standard spaceships should be found in a p2 search, etc.

A search for a glide symmetric spaceship of period 8 would be akin to a period-4 asymmetric search of the same width. From what I've seen, glide-symmetric ships do not seem to be too much thinner than a bilaterally-symmetric ship of the same speed.

... But if you add a glider in just the right place, you'll get a loafer. I've removed the glider in case anyone wants to try and figure it out -- but I'm afraid this kind of puzzle will never replace Sudoku. There's actually a big hint in the RLE, if you need one. Experimentation to find the various one-time-turner chains is a good idea, of course, but no fair using a script like pd-glider.py to find the answer for you. If you're going to do that, just try the pattern below instead: